Introduction:

Sexual orientation and gender identity have some biological bases based on genes, perinatal hormones and brain dimorphisms that have been studied in recent decades. The objectives of this study are to know the psychometric properties of a questionnaire to evaluate biological knowledge of homosexuality and transsexuality and to investigate such knowledge in a Chilean sample.

Methodology:

144 people from three regions of Chile were surveyed. A sociodemographic survey and the Biological Knowledge of Homosexuality and Transsexuality Questionnaire (BKHT) were applied.

Results:

The results show that the instrument is valid and reliable for the sample used. It is also noted that 75,7% of the respondents obtained between 1 and 6 correct answers out of a maximum of 18. Of the sociodemographic variables, only religious beliefs and having dealt with homosexuality and transsexuality in their sex education classes are predictors of the BKHT scores.

Conclusions and Recommendations:

BKTH is valid and reliable to be applied in Chilean population samples. The sample evaluated has low levels of knowledge about the biological basis of homosexuality and transsexuality. It is recommended to replicate this research in larger samples, in other regions of Chile and in other Latin American countries.